What is ISiTGR?

ISiTGR is an integrated set of modified modules for the software package CosmoMC for use in testing whether observational data is consistent with general relativity on cosmological scales. It incorporates modifications to the codes: CAMB, CosmoMC, the ISW-galaxy cross correlation likelihood code of Ho et al, and our own weak lensing likelihood code for the refined COSMOS 3D weak lensing tomography of Schrabback et al to test general relativity. It also includes our generalized BAO likelihood module which uses the recently released WiggleZ BAO data of Blake et al.

A detailed explanation of the modifications made to these codes allowing one to test general relativity are described in our paper.

How to get ISiTGR

Two versions of ISiTGR are available. The normal version of ISiTGR uses a functional form to evolve the parameters used to test general relativity and is available here. ISiTGR_BIN, on the other hand, gives you two options to evovle the parameters used to test general relativity. The first option is to bin the parameters in two redshift and two scale bins, alternatively one can use the hybrid evolution method, as seen in our paper, where scale dependence evolves monotonically, but redshift dependence is binned. That code can be downloaded here.

To run ISiTGR you must first download and install CosmoMC (August 2011 version). You can find download instructions, system requirements, and setup instructions for CosmoMC in the CosmoMC ReadMe. Then, simply copy the contents of the unzipped ISiTGR folder to the CosmoMC folder, edit the Makefile for your compilers, compile (extra compiling step here), and you are ready to go. Detailed explanations of the specific options available in each of the ISiTGR codes are availalble in the ISiTGR ReadMe.

Referencing ISiTGR.

We would ask that when using ISiTGR or a modified version of it, you cite: our paper, this website; the original CAMB paper; the original CosmoMCpaper; and the papers on original ISW-galaxy cross correlation likelihood by Ho et al and Hirata et al. If the refined HST COSMOS 3D weak lensing tomography likelihood in our code is used, the papers by Schrabback et al., Scoville et al., and Ilbert et al should be cited. When using the WiggleZ BAO likelihood module please cite the paper of Blake et al. Additionally please cite the use of any other datasets already included in the original version of CosmoMC.